It is known that fluid-tightness can be established between tubes carrying fluids, especially gases, by fixing complementary conical metal elements to the tubes, these elements being held tightly against one another in the sealing position by means of a two-part casing.
Numerous accidents occur every year as a result of loosening of the two parts of such a casing, for example under the effect of vibration.
In addition, fluid-tightness requires that the screw-thread by which the two halves are assembled should be cut very accurately. This accuracy is goverened by various national Standards, for example, French Standard NF 03004 (October, 1970), such accurancy involves precision machining and, hence, additional cost.
In another field of use, it has already been proposed to avoid the premature loosening of the two coupling elements by providing them with a permanent magnet, fluid-tightness being obtained by traditional plastic elements. See, for instance, U.S. Pat. No. 2,793,057.
One object of the present invention is to provide a novel fluid-tight coupling. Aother object is to provide a novel fluid-tight coupling which can be assembled easily and which provides for easy alignment of the tubes to be connected.